This invention relates to a system for detecting conductive contaminants interspersed within unconsolidated, primarily non-conductive materials. The conductive properties of the contaminants complete a detectable electrical circuit. In addition, a method of using this system allows for the removal of potentially dangerous or harmful conductive contaminants from the unconsolidated materials.
Waste recycling companies and waste management companies have searched for new technology to detect and remove harmful conductive contaminants interspersed within nonconductive, unconsolidated materials. For example, nails, aluminum cans, and metal refuse are often discarded in composts, soils, or waste materials. Likewise, hypodermic needles, razors, or similar potentially hazardous contaminants may also be discarded within these unconsolidated materials. As such, it is preferably to remove these contaminants before the waste materials are recycled to provide source materials for potting soils, fertilizers, and other similar useful products.
Unfortunately, and despite the waste-recycling companies"" best intentions, these now-useful materials occasionally include portions or remnants of these harmful and dangerous conductive contaminants. Due to the volume of unconsolidated materials that must be scrutinized for these conductive contaminants, it has been admittedly difficult to screen or search for these conductive contaminants. Countless tons of unconsolidated materials have not been recycled out of fear that conductive contaminants remaining therein could harm or otherwise injure those attempting to use these recycled materials.
In fact, recycled materials that contain conductive contaminants have harmed innocent users. For example, purchasers of these recycled materials have risked the danger of being harmed by nails, cans, or similar items that were interspersed within these unconsolidated materials. In an extremely dangerous situation, it is conceivable that users of these recycled products could encounter a discarded hypodermic needle that could be contaminated with an infectious disease.
Waste recycling companies have devised or used various methods of detecting these conductive contaminants with marginal success. For example, it is possible to visually inspect small amounts of unconsolidated material for these kinds of conductive contaminants. Due to the nature of the unconsolidated materials and the size of the conductive contaminant, however, this type of search is literally xe2x80x9clooking for a needle in a hay stack.xe2x80x9d Due to the excessive volume of materials that must be screened, a visual inspection is impractical and inefficient.
In the alternative, the prior art described sifting techniques that would capture larger objects while allowing granules such as sand to pass through a sifter or a series of sifters. This method is particularly inappropriate when the unconsolidated material comprises branches, twigs, or similar structured materials that cannot pass through the relatively small holes of the sifters. Moreover, a strategically placed needle or similar conductive contaminant could theoretically pass through the sifting screens without being detected or removed.
Therefore, a serious need exists to provide a system and a method of using this system that can manage the voluminous amounts of unconsolidated materials that must be screened for these conductive contaminants such as nails and needles.
The present invention provides a system to detect the conductive contaminants interspersed within unconsolidated materials. By using the system described herein, voluminous amounts of unconsolidated materials such as soils, waste streams, hay, and similar non-conductive materials may be processed such that conductive contaminants, namely metal objects, may be identified and removed from the processed material.
Though many variations of the present invention will be evident to those skilled in the art, the present invention utilizes the conductive property of these contaminants to alert the system such that the contaminant may be removed. By passing the unconsolidated waste materials across an arrangement of alternatingly charged contacts placed in close proximity, metal or similarly conductive contaminants will complete an electrical circuit that may be detected by a sensor that alerts or otherwise indicates the presence of the conductive contaminant and initiates a shut down procedure.
In an alternative embodiment of the invention, this alerting system comprises a neon light incorporated into the electrical circuit that emits light when the circuit is completed by the conductive contaminant. When a light detector detects the emission of light, it triggers a relay to halt the processing of material as described herein. This system and its method of use may be adapted to detect conductive contaminants in voluminous, unconsolidated materials for a variety of applications.
The foregoing has outlined rather broadly the features of the system and method of the present invention so that the detailed description of the invention that follows may be better understood. Additional features and advantages of the invention will be described hereinafter which form the subject of the claims of the invention. Those skilled in the art should appreciate that the conception and the specific embodiments disclosed may be readily used as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.